Detection of serum proteins by native polyacrylamide gel electrophoresis using Blue Sepharose CL-6B-containing stacking gels

Department of Clinical Biochemistry, Kyorin University School of Health Sciences, Miyashita, Hachioji, Tokyo, Japan.
Analytical Biochemistry (Impact Factor: 2.22). 09/2002; 307(2):337-40. DOI: 10.1016/S0003-2697(02)00052-0
Source: PubMed

ABSTRACT Analysis of serum proteins by native polyacrylamide gel electrophoresis is difficult because albumin is abundant in serum and interferes with the resolution of other proteins, especially alpha-antitrypsin which has mobility that is very similar to that of albumin. We present here a method in which serum proteins are separated by polyacrylamide gel electrophoresis using stacking gels containing Blue Sepharose CL-6B, which has a high affinity for albumin, lipoproteins, kinases, and pyridine-nucleotide-dependent oxidoreductases. During electrophoresis, proteins that bind to Blue Sepharose CL-6B stay in the stacking gel and do not migrate into the separating gel. As a consequence, certain proteins, including alpha(1)-antitrypsin, can be detected as clear bands. This method overcomes the requirement for fractionation of serum samples prior to electrophoresis to remove albumin and allows the simultaneous analysis of many samples.

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